Hello everyone! Welcome to advanced neurobiology!
Neuroscience is a wonderful branch of science on how our brain perceives the external world, how our brain thinks, how our brain responds to the outside of the world, and how during disease or aging the neuronal connections deteriorate. We’re trying to understand the molecular, cellular nature and the circuitry arrangement of how nervous system works.
Through this course, you'll have a comprehensive understanding of basic neuroanatomy, electral signal transduction, movement and several diseases in the nervous system.
This advanced neurobiology course is composed of 2 parts (Advanced neurobiology I and Advanced neurobiology II, and the latter will be online later). They are related to each other on the content but separate on scoring and certification, so you can choose either or both. It’s recommended that you take them sequentially and it’s great if you’ve already acquired a basic understanding of biology.
Thank you for joining us!

Enseigné par

Yan Zhang

Professor

Yulong Li

Research Fellow

Transcription

And, if there are more than one resistance, okay, then it depends on whether they are in parallel or in series, tangent, okay? The current can be described similarly, okay? So, in, let's just for the fun, for this simple one. In this case, if the resistance are in series, then the current is equal to, this big R is equal to the R1 + R2. Okay, great. And then, there’s another important component which we call capacitor. And, the capacitor Is another essential component for the electrical circuit, okay? And, how we describe the current going to the capacitor in a circuit? Okay. Okay, it's a very simple, okay? The capacitor needs time to get in charge okay? So initially, when this circuti was on, okay, there is no charge across the capacitor okay. The current will be the biggest, okay? And then, over time, the capacitor will get charged, okay? And, that would generate voltage across this capacitor, okay? Which, in turn, will lower the driving force and amount of current to charge this capacitor. Okay, and eventually when this capacitor is a fully charge, you will have the same wattages across this battery, the same. And, the net current in the circuit is going to be zero. We are going to look at that inside a neuron. And see, what is the relevance for this simple Ohm's Law in the capacitora, okay? So, this describes the same thing, if you have the resistance in the capacitors again initially if you look at the top. Initially, the current, how the current will change. The current will become lower and lower because, initially the capacitor is not charged, the risk capacitor is as if, it does not exist, all the current will go through to charge it. And the current is only determined by the resistance in this case. But once the capacitor is getting charged and charged, the current goes down in exponential fashion, lower and lower, okay? How do we do that, to study the membrane, or a membrane of a neuron? Well, a membrane, a cell membrane can be think of a composition of special resistance and capacitance and it's just their combination, whether it's in series or in parallel. And again, we mentioned that Hodgkin and Huxley make the most fundamental contribution using a special animal squid, giant squid [FOREIGN] okay? And in fact, many neuroscientists worshipped these two great neurophysiologists, okay? So especially, they not only illustrate the mechanism of action potential, they are great experimentalists. They generally their, or they modify their own apparatus instruments to do those measurements. For example, to this day, some labs are still using the micro manipulator designed by Andrew Huxley, okay? That can make fine movement of the electrode, okay?